debian-mirror-gitlab/lib/api/helpers/pagination_strategies.rb
2021-11-11 11:23:49 +05:30

79 lines
2.6 KiB
Ruby

# frozen_string_literal: true
module API
module Helpers
module PaginationStrategies
def paginate_with_strategies(relation, request_scope = nil)
paginator = paginator(relation, request_scope)
result = if block_given?
yield(paginator.paginate(relation))
else
paginator.paginate(relation)
end
result.tap do |records, _|
paginator.finalize(records)
end
end
def paginator(relation, request_scope = nil)
return keyset_paginator(relation) if keyset_pagination_enabled?
offset_paginator(relation, request_scope)
end
private
def keyset_paginator(relation)
if cursor_based_keyset_pagination_supported?(relation)
request_context_class = Gitlab::Pagination::Keyset::CursorBasedRequestContext
paginator_class = Gitlab::Pagination::Keyset::CursorPager
availability_checker = Gitlab::Pagination::CursorBasedKeyset
else
request_context_class = Gitlab::Pagination::Keyset::RequestContext
paginator_class = Gitlab::Pagination::Keyset::Pager
availability_checker = Gitlab::Pagination::Keyset
end
request_context = request_context_class.new(self)
unless availability_checker.available?(request_context, relation)
return error!('Keyset pagination is not yet available for this type of request', 405)
end
paginator_class.new(request_context)
end
def offset_paginator(relation, request_scope)
offset_limit = limit_for_scope(request_scope)
if (Gitlab::Pagination::Keyset.available_for_type?(relation) ||
cursor_based_keyset_pagination_supported?(relation)) &&
offset_limit_exceeded?(offset_limit)
return error!("Offset pagination has a maximum allowed offset of #{offset_limit} " \
"for requests that return objects of type #{relation.klass}. " \
"Remaining records can be retrieved using keyset pagination.", 405)
end
Gitlab::Pagination::OffsetPagination.new(self)
end
def cursor_based_keyset_pagination_supported?(relation)
Gitlab::Pagination::CursorBasedKeyset.available_for_type?(relation)
end
def keyset_pagination_enabled?
params[:pagination] == 'keyset'
end
def limit_for_scope(scope)
(scope || Plan.default).actual_limits.offset_pagination_limit
end
def offset_limit_exceeded?(offset_limit)
offset_limit > 0 && params[:page] * params[:per_page] > offset_limit
end
end
end
end